A chain with links made from case-hardened D-profile steel lengths is shown in EP 0 816 717 B1, where each link has a substantially planar outer circumferential area in which two side flanks open by forming a sharp edge or a rounded portion with a very small radius of curvature. As a result, only a very low reduction in the profile cross-section of the links is achieved, so that large moments of resistance to bending can be achieved. The maximization of the cross-sectional area is reflected in an increase of the chain tension force and the moments of resistance to bending. Large moments of resistance to bending lead to a high dynamic strength of the chain.
The links of the chain shown in EP 1 440 253 B1 are also made of D-profile steel lengths, in which the rounded portions in the region of the transition between the side flanks and the planar circumferential area are provided with a rounding radius which is equal to 0.2 to 0.4 times the value of the distance between the flanks of the links. This rounding radius, which is larger in comparison than the links of the specification mentioned above, also not only leads to a respectively larger reduction in the cross-sectional area of the profile of the link and thus not only to a certain decrease in the tensile force of the chain, but also to a reduction in the moments of resistance to bending, which on its part leads to a reduction in the dynamic strength of the chain.